Air heater



Dec. 3, 1935. R Q ROE 2,022,812

AIR HEATER l Filed Oct. 25, 1932 2 Sheets-Sheet 1 IIIIIIIIIIII -'L 3 as mff'QQUQGQSG-gg 20 I UOUUUU- UUUUUJ R. C. ROE

AIR HEATER Dec. 3, 1935.

Filed 00T.. 25, v1932 2 Sheets-Sheet 2 Patented Dec. 3, 1935 UNITED STATES PATENT OFFICE AIR HEATER Application October 25, 1932, Serial No. 639,451

4 Claims.

The present invention has for its object to produce a simple, novel and inexpensive device for storing heat which is later to be released for heating the air of a room and especially a device wherein the heated air is tempered by being mixed with cooler air before it is released into the room and wherein the air now through the device is maintained by thermo action and regulated by varying the area of the air passages. Other objects will appear from the description and the drawings, wherein:

Fig. 1 is a plan view with part of the exterior casing broken away and with the insulating stopper I6 removed. Fig. 2 is an elevation, partly in section on the line 2, 2 of Fig. l and showing the insulating stopper I6 in the full open position.

Fig. 3 is a vertical cross section on the line 3, 3

of Fig. 1. Fig. 4 is a view of the power unit taken on the une 4, 4 of Fig. 1. Fig. 5 is an enlarged top view on the line 5, 5 of Fig. 2. Like symbols indicate like parts.

Referring to the drawings, I0 is a metal container. Within the container and extending through the top and bottom thereof, are a number of metal tubes II. ,The container is partially iilled with heat storage substance I2, and hermetically sealed. In some cases the container containsalso an inert gas, as I3, on top of the substance.

Completely surrounding the container I0 is an enclosure I4, constructed of heat-insulating material. Between the container I3 and the enclosure I4 'is a vertical airway I5 in which are located a series of radiating fins 33, attached to the container Ill. Inside the tubes II there are located a number of fins 31, extending lengthwise of the tubes.

That portion of the insulating enclosure I4 which is directly above the container I9 and airway I5, is removable and forms a stopper I3. The stopper is attached to the number 30 which is actuated by motor 3I so as to raise and lower the stopper. The motor 3| is provided with current by circuit 32 via the switching mechanism 34 which mechanism may be controlled by a thermostat as 33. The lines 35 and 33 represent whatever wiring may be necessary for the purpose.

An exterior casing I1 encloses the other parts and is provided with openings as I3 and I3 for the admission of air to be heated and forming at the top a mixing chamber with openings, as 20, for the exit of tempered air. Between the enclosure I4 and the casing I1 is an air passage 2 I, provided with an air deector 39, which may be stationary or adjustable. The container I0 and (Cl. 21S-38) enclosure I4 are supported by members 22 which are attached to the casing I1, as by rivets 23. The container I3 may be welded to support 22 and the enclosure I4 rests upon plate 4I which is attached to member 22 by a bracket 4U.

An electric heater 24 is located within a pipe sleeve 25, which extends horizontally through the container III at a point near the bottom and lengthwise-of the container. The heater 24 is connected to the electric circuit 26, which may 10 be time controlled, and which is controlled by a switching device 28 which in turn is controlled by the thermostat 2l which is located in heat exchange relation with the heat storage substance I2. The line 29 represents whatever wiring is necessary between the thermostat and the switch 28.

There are several substances which may be used for storing the heat but one of the best is made up of sodium chloride (NaCl), magnesium chloride (MgCl2) and potassium chloride (KCl) in proportions to g'ive a. melting point of about 330 degrees Fahrenheit. When in the presence of moisture this solution becomes corrosive and in order to exclude all air or other source of moisture from container I0, I replace the air with an inert gas such as' argon or helium. Preferably sufcient gas is introduced so that a slight pressure above atmosphere will exist when the heater is at its lowest temperature. Expansio-n of the solution with increase in temperature is compensated for by compression of the gas. The solution has a boiling point, at atmospheric pressure, well above 1200 degrees F. at which maximu'm liquid temperature the device herein described has been designed to operate. The specic heat is about .7.

With the high temperatures and speciiic heat available it is possible to store a relatively large amount of heat in a given space. The heat requirements of an ordinary living room, for instance, may be supplied by a heater having an overall content of about 12 cubic feet. The heat may be stored over a period of about6 hours, say from l2 midnight to 6 A. M. and delivered to the room during the balance of the day.

In the preferred solution, in addition to the specific heat, there is available the latent heat of fusion which further increases the heat stor- 5 age capacity in its relation to size of apparatus. This is true of any usable solution whose fusion temperatures are suiciently higher than maximum, desirable room temperatures to provide necessary heat head. In the case illustrated, the working temperature range could readily be say ting off the source of heat. When heat is drawn from the device, the temperature of the solution will drop until a predetermined lower temperature is reached when the thermostat 21 will cause the electric heater to be reconnected to the supply circuit.

When it is desired to release heat it is only necessary to raise the stopper I6. 'I'he heated air in the passages Il and I5 will move quickly upwards which will cause an inflow of cool room air into the bottom of the tubes via the openings I8 and I9. As the very hot air passes out the oriilce between the stopper I6 and the enclosure I4 and thence generally upwards, it creates a suction at the outlet of the cold air passage 2|. Thus the very hot air coming from direct contact with the highly heated surfaces and which therefore may be dangerously hot, is mixed with cold room air before it is ejected into the room. The proportions of the mix may be easily adjusted by adjusting the area of the cold air outlet, which may be conveniently done by adjusting the deector 39, or by otherwise varying the relative sizes of the outlets of the hot and cold air passages. The fins 31 and 38 increase the amount of heat which will be taken up by a given amount of air thus producing higher air temperatures and resulting in a more rapid flow of air thereby increasing the maximum rate at which the device will deliver heat to the room.

When the room air has attained a suitable temperature the flow of heat from the heater is stopped by lowering the stopper I6 into the opening at the top of the container I0, which opening it is designed to fit snugly, the t being improved by its tapered construction. This shuts oi the circulation of hot Aair via spaces II and I5 and also the radiation from the top of container I0.

The stopper I6 may be raised and lowered by hand or by power, as by an electric motor, and if by motor the motor may be easily controlled by a thermostat located so as to be responsive to the room temperature. Any of the methods and refinements of regulation associated with the thermostatic control of ordinary house heating equipment may be employed so far as they are applicable.

It is to be understood that the thermostat 33 may be attached to the outside of casing I1 and that all the wiring and all the devices as 28 and 34 may be located within the casing I1, as may also the terminal of thermostat 21, heater tube 25 and heater 24, the circuits 26 and 32 terminating in a suitable connection fitting attached to the casing I1.

Since the heater need not be structurally connected to any part of the building except by an electric circuit, it is obvious that it may be arranged in portable form, which form is very desirable for many uses, its usefulness as such being greatly increased by its ability to give oiI a large amount of high temperature heat in a relatively short time.

While I have illustrated and described with particularity only a single preferred form of my invention, I do not desire to be limited to the exact structural details thus illustrated and described; but intend to cover all forms and arrangements which come within the denitions of my invention constituting the appended claims.

I claim:

1. An air heater which includes: a container; heat storage substance in the container; means for heating the substance; an enclosure of heatinsulating material for the container; a casing for-the enclosure including a mixing chamber near the top of the enclosure having air exit apertures, and including air inlet apertures below the enclosure; a vertical airway within the enclosure, Said airway being arranged in heat exchange relation with the heat storage substance, and extending through the enclosure at the bottom of the container and extending into the mixing chamber; means for controlling the ilow of air from the airway into the mixing chamber; and a vertical cold air passageway exterior to the enclosure and within the casing and terminating in the mixing chamber for conveying cold air to the chamber for tempering the heated air.

2. In a heater as dened by claim 1, means for regulating the ilow of cold air.

3. In a heater as dened by claim 1, an inert gas hermetically sealed in the container with the heat storage substance.

4. A heater according to claim 1 characterized by the fact that the heat storage substance is sodium, magnesium and potassium chlorides in any proportions which will give a melting point of about 330 degrees Fahrenheit.

RALPH C. ROE. 

